Tuesday was quite the decisive day in American politics. Not only did Donald Trump win big in the Indiana Primary, but Ted Cruz also finally threw in the towel and suspended his presidential campaign. Today John Kasich is reported to be withdrawing from the race as well, leaving Trump in an uncontested position for the Republican nomination.

What Paul Krugman calls “Movement Conservatives” – those who support the increasingly right-wing trajectory of American conservative policy from Barry Goldwater’s run for the presidency in 1964 through the Reagan presidency of the 1980s and on through the Tea Party era – these “true” conservatives must be shaking their heads in disbelief now that Ted Cruz, their last standard-bearer of conservative ideology, has given up the fight in this year’s presidential race.

In one audacious and masterfully crafted campaign Donald Trump has single-handedly swept aside the carefully constructed coalition of conservative interests that have defined Republican ideology for the past 40 years. The prevailing Republican strategy since the Nixon presidency has been to craft an alliance between a hard-core anticommunist faction, those opposed to new civil rights legislation, and those promoting a governmental “hands off” approach to economics.

This “three-legged stool” of core Republican principles, as Josh Barro refers to them, namely militarism, social conservatism and libertarian economics, has now been replaced by Trump’s inflammatory rhetoric focusing on immigrants, Muslims, and the very rich.

Trump’s rejection of traditional Republican ideology in his campaign is remarkable. With regard to America’s military policies, Trump has denounced G. W. Bush’s war in Iraq, and called into question America’s continuing support for NATO. In a recent speech laying out his vision for America’s role in the world Trump decried what he called “the dangerous idea that we could make western democracies out of countries that had no experience or interest in becoming a western democracy.”

On social issues Trump long ago carved out a liberal position that strongly departs from official Republican policy. In 1999 he stated on Meet the Press that he was “very pro-choice” and the same year he stated in an interview with Larry King that he was “very liberal when it comes to health care” and that he believed in “universal healthcare.”

In a major departure from traditional Republican economic policy, Trump has argued that the wealthy get too many tax breaks and they should be required to pay more. He has denounced America’s international trade agreements, which he claims have not created more jobs for Americans but taken them away. He has defended existing social entitlements and has pledged to leave Social Security Medicare and Medicaid benefits intact.

Donald Trump has repudiated a slew of core Republican policies and harshly criticized the Republican National Committee itself. He has thumbed his nose at attempts within to RCN to deny him the party’s candidacy, and in all of this he has prevailed.

The question now is, with Trump poised to claim the Republican Party nomination at its upcoming convention, will the party establishment come around to aligning itself with Donald Trump? Trump has emerged as a polarizing figure both within and beyond the Republican Party. Polls show that fully two-thirds of Americans give him an unfavorable rating, a number that has “no equal among major party nominees in presidential campaigns over the last 23 years.” And so, if Trump loses badly in this fall’s election (as many expect will happen) will the party itself lose credibility in aligning itself with him and his nonconformist policies?

A new reality has now dawned for the Republican Party: In consolidating his standing as the sole remaining party candidate as an outlier, Donald Trump is well on his way to overseeing the destruction of the Republican brand and, some contend, possibly the destruction of the Republican Party itself.

And so far Republican insiders have been able to do nothing to stop it.

Edward Clayton grew up in the US but has lived in Canada for the last 4 decades. He is a long time peace activist and committed to issues of social justice and good government. He reports on Canadian, American, and global politics from a Canadian perspective.